This invention is directed to the formation of one or more channels into the wall of a patient's heart and particularly to the intraoperative formation of such channels in the heart wall. These channels may be used to increase blood flow to heart tissue experiencing ischemic conditions and for the delivery of therapeutic or diagnostic agents to various locations.
The formation of channels to increase the blood to flow to a patient's heart tissue is called myocardial revascularization. The first clinical trials of the revascularization process was made by Mirhoseini et al. See for example the discussions in Lasers in General Surgery (Williams & Wilkins; 1989), pp 216-223. Other early disclosures of this procedure is found in an article by Okada et al. in Kobe J. Med. Sci 32, 151-161, October 1986 and U.S. Pat. No. 4,658,817 (Hardy). These early references describe intraoperative revascularization procedures which require an opening in the chest wall and include formation of the channels through the epicardium.
Copending application Ser. No. 08/361,787, filed on Dec. 20, 1994 (Aita et al.), now U.S. Pat. No. 5,554,152 which is incorporated herein in its entirety, describes an intraoperative system for myocardial revascularization which is introduced through the chest wall. While the intra-operative system for performing revascularization, developed by Aita et al., was a substantial advance, one of the difficulties in developing intraoperative channel forming devices was to provide an intraoperative device which was flexible enough to be manually positioned within the patient's chest cavity and yet be constructed of sufficient strength to maintain its integrity and to preclude loss of the distal tip of the optical device, particularly within the patient's heart, during the procedure. Another difficulty with prior channel forming devices is the difficulty in forming channels on the posterior side of the patient's heart. The present invention minimizes the difficulties of the prior channel forming devices.